A review of microbial degradation of per- and polyfluoroalkyl substances (PFAS): Biotransformation routes and enzymes

Impact of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) on secondary sludge microorganisms: removal, potential toxicity, and their implications on existing wastewater treatment regulations in Canada

“…In terms of removal through biodegradation/ biotransformation, research has predominantly been focused on the polyuorinated PFAS, and the data is limited for the peruorinated ones. 29,30 Recent reviews by Zhang et al (2022) 30 and Berhanu et al (2023) 29 provide extensive microbiological data on the biodegradation pathways of both peruorinated and polyuorinated PFAS. In the current review however, the authors aim to present the existing relevant data on microbial peruorinated PFAS degradation that pertains to secondary sludge and wastewater treatment.…”

Climate‐influenced hydrobiogeochemistry and groundwater remedy design: A review

“…The work assessing PFAS degradation under various biological and redox regimes also has a climatic component because of their general stability and long‐term persistence in the environment. This is an important topic not just because of the potential degradation of PFAS directly or indirectly from current or future biological processes (Berhanu et al, 2022; Zhang et al, 2021), but also because some PFAS and PFAS precursors (i.e., compounds that have the ability to form PFAS) have potential to transform to constituents that may have different and more challenging toxicological, mobility, and fate profiles (Liu & Mejia Avendaño, 2013; Shahsavari et al, 2021). Finally, an important consideration that exists regarding PFAS is whether the global distribution and occurrence of these chemicals in the environment will continue to be exacerbated by shifting climatic (e.g., wind patterns and extreme events) conditions because of their relative stability and very slow (if not negligible) degradation under ambient environmental conditions (Newell et al, 2022).…”

Vacuum-UV Radiation Capable of Catalyst-Free Decomposition of 6:2 FTSA: The Transformation Mechanism and Impacts of the Water Matrix

“…At the same time, a number of reports revealed the overwhelming contribution of 6:2 FTSA in the impacted environments in the USA, , Canada, , and Europe, − where the concentration of 6:2 FTSA was ∼6 to 14-fold higher than the concentrations of regulated PFAS, such as PFOA. , More importantly, the occurrence of 6:2 FTSA has been reported in treated drinking waters, , where for instance, 37% of all tap water samples tested in Canada had a detectable amount of 6:2 FTSA . Further, telomer-PFAS such as 6:2 FTSA have been established as precursors to persistent fully fluorinated PFAS associated with elevated aquatic risk. ,, Thus, in general, they play a critical role in worldwide PFAS pollution, and their fate, transformation, and degradability should be the focus of more research. It is worth mentioning that recent studies have shown much slower removal and decomposition kinetics of telomer-PFAS than that of perfluorinated carboxylic/sulfonic acids (PFCAs/PFSAs) using ion exchange resins and the UV/sulfite process, warranting the pressing need for appropriate treatment processes for this class of PFAS.…”

“…17 Further, telomer-PFAS such as 6:2 FTSA have been established as precursors to persistent fully fluorinated PFAS associated with elevated aquatic risk. 16,18,19 Thus, in general, they play a critical role in worldwide PFAS pollution, and their fate, transformation, and degradability should be the focus of more research. It is worth mentioning that recent studies have shown much slower removal and decomposition kinetics of telomer-PFAS than that of perfluorinated carboxylic/sulfonic acids (PFCAs/PFSAs) using ion exchange resins 20 and the UV/sulfite process, 21 T h i s c o n t e n t i s warranting the pressing need for appropriate treatment processes for this class of PFAS.…”